Storage-battery-charging switch for automobiles.



vAE1-1112515.|35: 'Y

E: BISBMANN. .y

STORAGE BATTERY OHABGINGSWIVTGH FOR. AUTOMOBILES;

' 'APPLIOATION 'FILED No.v. ,9, 1911. 1. 25,"O80n Patented Jau-19,1915.

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STOKAVGATTEYQARGNG SWITCH FOR AUTOMOBILS.

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Speciication of Letters Patent;

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applicaties aiea November e, i911. seri-ai no'. statica'.

i To all fwiom it may concern Be it known that I, ERNST ErsnMANN, a subject of the German Emperor, and residing at Stuttgart, Germany, have invented certain new and useful Improvements in Storage-Battery-Gharging Switches for Automobiles, of which the following is a specification. a

The subject-matter of this invention is a storage battery charging switch which not only automatically cuts the charging machine into and out of circuit when the charging voltage exceeds or does not reach a predetermined amount, but also automati-` cally disconnects the charging machine as soon as the accumulator battery has reached its maximum voltage.

My improved switch substantially consists .of armatures whichcan oscillate in polarized fields, control contacts and, whenlthe voltage of the charging dynamo is equal to the normal charging voltage, are set in the polar axes and thereby close the said contacts, whereas when the normal charging voltage is not attained, the armatures are placed by springs transversely of the v field and thereby open the said contacts, and

when the maximum charging voltage of the battery is exceeded, the armatures are likewise placed transversely of the eld and permanently break the circuit.

lTwo illustrative embodiments of the invention are represented by way of example in the accompanying drawings, wherein Figure 1 is a vertical longitudinal section showing one form; Figs. 2 and 3 are top' plan views showing the same in two difierent positions of the armature; Fig. 4 is a diagram of connections, and Figs. 5 to 7 show the second form of switch diagrammatically.

Referrin firstly to Figs. 1 to 4, A desig- -nates an e ectromagnet having a winding A and which is designed so that the magnetic induction is on the rapidlyrising branch of the magnetization curve, so that smallchanges of voltage and, with it, of the strength of current in winding A bring .Two pole pieces B conduct the lines offorce about relatively large changes in the lines of force inthe `winding of this magnet.

'through the .rotatable armature C. An 'arm D .carrying av platinum contact E is 'rigidly connected with the armature. The armature is underrthe inuence of' a spring F'whichtends to place it transversely ofthe field in such manner that, as shown in Fig.

. 3, the contact E of the arm D is separated from the contact L and the arm D bears against a fixed stop L. The armature carries two windings, one winding G of fewV turns of` thick wire capable of' being connected in series with the chargingV dynamo J, through contacts L and E and one winding of many turns of thin wire capable ofbeing connected in shunt with the charg- .ing machine by relay contacts N and O.

The winding G normally aids the action of the iield of the electromagnet A in such manner that the armature endeavors to set itself in the polar axis, whereas the winding H reduces the action of the polar field as soon as it is traversed by current, so that'y voltage of the battery K or the generator J a suiiicient number of lines of force will pass from one" pole of the magnet to the other through the air to cause the arm of the relay M to be attracted by the magnet at its free end thus closing the contacts N and O as shown in Fig. 3. The relay M is so regulated` that it remains open until the maximum charging voltage of the battery obtains, but then. closes owing to the increasing magnetic force of the electromagnet A and thereby connects the winding H into circuit.

The operation of the switch is as foilows:-The magnetic relay being opened., when the charging dynamo J starts and has reached the terminal voltage requisite-for charging, the winding A excites the electroinagnet A sufiiciently to drive the armature C against the action of its spring l" from its rest position (Fig. 3l into the circuit-closing position (Fig.` 2), whereupon the platinum contact E bears against the contact L and closes the circuit. The bat- `tery K and the series winding G are now connected in circuit as appears clearly from lVhen, howvse Fig. 4. As the winding G aids the action of the magnet A, while the terminal voltage of the machine J increases, the pressure between the contacts E and L increases; if,A

on the contrary, the terminal voltage falls below that of the battery so that a current fiows back from the battery to the dynamo, the winding Gr weakens the field of the electromagnet A to such an extent that the action of the spring l" preponderates and the armature C sturned, z'. e. the contacts E and L ai'e parted. r[he armature closes the circuit again as soon as the voltage of the charging dynamo hasagain exceeded that of the battery by the requisite amount. Vhen the battery K has reached its maximum voltage, however, the correspondingly regulated relay M is operated yin such umanner that the contacts N and O contact one another, and .the Winding H which reduces the field of the electromagnet A is thrown into circuit. The armature C then rotates under the action of its spring into the rest position, thereby interrupting the circuit at contacts L and Il. As soon as this interruption o'l the main circuit has taken place the terminal voltage of the charging dynamo rises to its maximum value and the field of the magnet A due to the winding A tends to increase correspondingly. l'ut as the current traversing the shunt Winding H increases correspondingly and simultaneously opposes the passage of the magnetic lines through the armature C and the field, the armature C remains in its rest position under the action of the spring F.

The illustrative embodiment according to Figs. 5 to 'I differs from that just described in that, instead of one oscillating armature carrying a contact, two armatures each carrying a contact are provided.

In Fig. 5 the letter J again designates the charging dynamo, K the battery to be charged, A an electromagnet whose winding A is permanently connected to the terminals of the charging dynamo, and which is so designed that the magnetic induction is' located on the rapidly rising branch of the curve of magnetization, so that small changes of the voltage and, with it, oi. the current iii winding A produce considerable changes in the lines of force. In contradistinction to the former 'foi-m, the magnetic field 'has 'four poles, so that there are two pairs of like poles Bl, B1 and B2, B2. Between each pair of opposite poles B1, B2 is journaled an. armature C1 and C2, respectively; these carry small levers D1, D2 havling Contact pieces E1, E2 which can bear against fixed contacts L1. L2 mounted on the trame. rlhese armatures C1, l, are held by spring pressure in the positions shown i-n Fig. 5. z'. c. the armature C1 transversely et' thel field so that the contact F11, L1 is broken,

the armature C? in the axis of the eldtso that the contacts E2, L2 contact. one another. The armature Ci carries a winding connected in series with the dynamo J and the aiinature C2 a winding H connected4 in shunt with the same.

rIhe inode of operation of the switch 4is as follows -If the terminal voltage of the machine J rises to the amount requisite for the charging of the battery, the. terminal voltage being in excess of the battu-y voltage, the strength of the field of the electromagnet increases to such :in extent that the armature tends to place itself in the axis of the field R, R and die contact-E1, L1 is closed. Current then flous yfrom the dy-,l

name through the winding reduces the field of the electromagnet' so4 that the action of the spring on the armature C1 preponderates and the contact E1, L" is opened. When the terminal voltage of the dynamo increases again, the circuit isl closed afresh, which operations arerepeated according to the relation oi the voltages of the battery and the charging dynamo. Vhen, on the other hand, the battery K at` tains its maximum chai-eine' voltafre the shunt winding fi cf the armature C2 is coner1 and the con' nected to the dynamo J by means of a relay y M which is connected in magnetic s hunt with the electromagnet A and has a Contactl i N adapted :to bear against a. fixed Contact O on the frame. 'Vhen this relay acts the armature C2 is placed by the electromagnetic action of the shunt winding H, trans-- versely of the field and the contacts E2, Lz are opened, wliereby the dynamo is disconnected frone the batteryl.y The spring l ol the relay is so designed that the relay M is closed only as soon as the battery has attained its maximum charging voltage. The contacts L2, E2 ythen remain open, because, on the one hand, when the terminal voltage of the dynamo increases the field of the magnet A increases. but on the other hand the electromagiie, ic action of the winding H likewise increases a certain amount. If, 0n the contrary, the dynamo J is stopped,

the relay M opens, the contact E1, Ll also opens, while the Contact L2, E2 closes, so.

that the original condition according to Fig. 5 again obtains.

I claim:-

. 1. vln 'a plant for charging accuiiiulatorm' the c oi'ril'iination, with a dviiamo. an'electromagnet 'having a winding ciii-iected in shunt therewith, and a storage battery hav ing one pole connected to one terminal of isa thg d namo, of a fixed contact piece con- A -1 necte to the other terminal of the dynamo,-

'an armature arranged to oscillate between A the poles of the said magnet and carrying 4 -a movable contact piece adapted to contact lwith the former contact piece when the armature'is located in the olar axis'of the .'magnet, said armature havmg a series windi' of the' polar axis of the magnet and to re ing having one end connected to the movable contact piece and the other end connected'to the other pole of the battery, and a spring tending to rotate the armature out move the movable contact from the fixed contact; a relay arranged in'magnetic" shunt with the said magnet, said armature carrying a shunt winding differential lto the Winding of said electromagnet, and l connected to the said fixed contact piece and to one Contact piece of said relay,l the otherl contact piece of the relay being connected to the former terminal ofthe dynamo.

2. The combination of a storage battery,

a source of current for charging the same,

and a controlling switch,said switch comprisingan electro-magnet having its winding in parallel with the said source and battery, an' armature attracted by the electromagnet, means for yieldingly opposing such attraction, a series winding on the armature, means controlled by the armature for vconnecting the series winding in circuit with the said source and battery when the armature is attracted by the electro-magnet, said series winding being energized by current owing from .the said source to the battery 'I to lassist the electro-magnet in holding the armature in Vattracted position, and energized to oppose the electro-magnet by a reverse flow of 'current 'whereby the series winding will beopen-circuited by the movement of the armature, a shunt Winding on the armature arranged in shunt relation to the said source of current, and means operated by the electro-magnet when the battery hasreached maximum voltage for connecting the shunt winding in circuit to cause the series winding. to be open-circuited andthecharging to be interrupted.

3. The combination of. abattery, a source of current connected therewith, and a cir- I cuit-controlling device comprising an electro-magnet having a winding in lparallel with the said source, a series Winding adapted to be connected in circuit with the said source and battery by the energizing of the electro-magnet at charging voltage of the said source vand to be-"automatically opencircuited whe'ntlie said source falls in voltage below the battery, a shunt Winding, and means actuated by the Delectro-magnet upon the maximum voltage of the charging current for connecting the said shunt across the terminals of the said source whereby the said series winding is open-circuited-and the charging of the battery interrupted. A

k4c. The combination of a source of current, a battery charged'therefrom,`and a circuit-controlling device, said ydevice comprising an electro-magnet having its windterminal of the battery and operating tooppose the attraction'of the electro-magnet on the armature when current Hows froml the battery to the said source-and thereby per-v mits the contacts to separate, a shunt wind- I ing'mounted on the armature, and a device controlled by the magnetic attraction of the electro-magnet when the voltage of the circuit is maximum for closing the circuit through the shunt winding whereby the latter opposes the magnetism of the electrmagnet and permits the said contacts to separate.

'5. A battery charging controlling switch comprising-an electro-magnet, an armature movably mounted with respect to the poles thereof, spring means connected with the armature for lholding 1t 1n a given position,

a lContact carried by the armature, a fixed contact on the electro-magnet to be engaged by the armature contact when the armature is attracted, a winding on the armature and connected y' in circuit by the said contacts,

whereby the flowof current in one directionr through the winding coperates with theI electro-magnet for holding the said armature in attracted position, and the'low of 'current in the opposite direction causes magnetic opposition to the electro-magnet to permit the said spring means to movel the armature and separate the said contacts, another Winding on the armature adapted when energized to oppose'the attraction of the electro-magnet on the armature, and means operated bythe electro-magnet when its attraction is maximum forconnecting I the last-mentioned winding of the armature in circuit. y

In testimony whereof, Iaiiix my signavvture in the presence of two witnesses.

Witnesses:

ERNEST E NTERMANN, FRIDA KLAIBER. 

